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Is contrived, while still in process substance some portion of a highly bonic acid), which, after the lapse s, of years, exerts unwelcome energy on-house. that the process by which diamonds laces of the earth cannot readily be

ly be imitated. But, in truth, the nmand are wholly incommensurable

universal manufactory; and—what him-the time during which those omparison with the long ages of the Infinite leisure of nature contrasts ments of a busy human life. The rown back upon his own resources, plainly the road for him to follow. must be by striking out a short way, track of natural operations. espretz attempted to form diamonds ricity on carbon in a vessel exhausted me months, during which a strong sing, the platinum wires constituting

to be covered with fine black dust he positive pole. This dust, when

found to contain octahedral crystals, burned without residue, and acted in der. This experiment was evidently

interest. Crystals so minute as to d eye could show no reason for their cordingly, this and similar attempts, necessful, were gradually relinquished aver, semi-extinct hopes have been hins been stimulated by an important

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of what has been called “synthetic Feil, of Paris, by a process, the details y the substance known to mineralogists upon, have succeeded, it is said, in produm,' and to jewellers, according to mixed with it, by the specific designato been crystallised artificially only

sapphire. This substance is, in fact, on a very small scale. The announcerdly fail to excite chemists to a still gly, a severe competition in diamond till occupies, many of the laboratories Rollox Works Glasgow, was the first

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competitor in the field, but received a check which obliged him to retire discomfited, though not vanquisbed. The crystals submitted by him for examination to Professor Story-Maskelyne (who seems by common consent to be appointed arbiter in the contest) were declared by that gentleman to answer none of the regular tests for diamond, and jewellers momentarily shook off their alarm at the threatened depreciation of their merchandise. A more formidable champion was, however, already at hand. On February 19th last Mr. Maskelyne wrote to the Times,' certifying that some small crystallised particles,' sent to him by Mr. J. Ballantine Hannay (who, like Mr. McTear, appears to be a Glasgow body'), possessed all the qualities of true diamond—they grooved a polished surface of sapphire, refracted light singly, and burned under the blowpipe on platinumfoil. No small sensation was created by this assurance on the highest authority, that a hitherto impregnable position had been triumphantly stormed by the advanced guard of chemical science, and a numerous and eager audience assembled, a week later, in the rooms of the Royal Society, to hear a preliminary paper read, in which the general principle of the discovery was unfolded.

It seems that the result obtained by Mr. Hannay, like many other important inventions, though unforeseen, was not accidental. In the course of some valuable researches on the solubility of solids in gases, he observed that certain substances, such as silica and alumina, which are insoluble in water at ordinary temperatures, dissolve in steam (or, to speak more correctly, in 'water-gas '), maintained at a great pressure and considerable heat. The idea naturally suggested itself to him that a solvent of a similar character might be found for carbon, which could then, in all probability, easily be obtained in a crystalline form. His expectations were indeed disappointed in this direction, but they were amply realised in another. When a gas containing carbon and hydrogen (say marsh-gas) is heated under pressure in presence of certain metals, he noticed that the hydrogen relinquishes the carbon to unite with the metal. It only needs the addition of a stable compound containing nitrogen, to compel the carbon, thus intercepted in a nascent state, to separate from its former companion in the shape of diamond. Although the part played by the nitrogen-compound has not yet been made quite clear, it is undoubtedly essential to the success of the operation.

The artificial production of diamonds is thus an accomplished fact, and modern science has added one more to its already numerous triumphs. But, while even

But, while even an imperfect acquaintance with Mr. Hannay's process adds to its speculative importance, from the valuable theoretical considerations involved in it, the practical objections to it are perceived to be very grave, if not insuperable. They are three-fold. First, the difficulty of constructing vessels strong enough to resist the enormous pressure and high temperature necess

15 On further investigation, Mr. Maskelyne invited a suspension of judgment as to the precise nature of the substance produced by Mr. McTear. It seems in fact to be far from uniform in its character. Certain portions of it are hard enough to scratch, not only sapphire but even diamond; and a proportion of crystallised carbon is undoubtedly present with the silica which forms its main constituent. Some slight modification of the process employed by him may not improbably lead to a less

essarily employed, wrought-iron tubes of four inches external diameter, and only half an inch bore, splitting like pasteboard in nine cases out of ten. Next, the fragmentary character of the crystals obtained—a circumstance possibly due (as suggested by Mr. Hulke) to the sudden and disruptive expansion, on the removal of pressure, of gases enclosed in the crystallising body. Last comes what is in truth the leading question of expense. Mr. Hannay's diamonds will not pay, and, from a commercial point of view, have consequently no existence. So long as jewels can be extracted from the sands of Bahia and the mines of Griqua-land at a cheaper rate than that at which they can be produced in the laboratory, trade will continue to flow in its old channels. Even this, however, may yet be accomplished. Mr. Hannay has carried off the crown of wild olive; but he has left the 500 drachmæ to be claimed by future competitors. And we may readily believe that they will not be lacking. Dr. Sydney Marsden, late of Sheffield, is said to be working actively in this direction, and we understand that Mr. Carl von Buch, of Christ Church, Oxford, has taken out a patent for the same purpose. From some hints relating to his method which have reached us, there seems no reason why it should not prove economical as well as effective, and so comply with the financial, no less than the scientific conditions of a prosperous issue.

It appears to be commonly lost sight of that these gems have a commercial value entirely independent of their decorative purpose. A peculiar modification of diamond, known as "carbonado,' which is as unsightly as cast-iron, is sold for use in rock-boring machines, at an average price of eighteen to twenty shillings the carat. Fifteen years ago an unlimited supply of this substance was offered to a London merchant, at the ridiculously low price of threepence a carat; the Amsterdam cutters, however, reported unfavourably as to its employment in their trade, and the proposal was declined. It was never renewed ; for shortly afterwards the serviceableness of the stone (which is as hard as diamond itself) both for rock-drilling and gem-engraving, was discovered, and from a drug in the market it became an object of energetic competition. “Carbonado' resembles in appearance certain meteoric stones of a blackish-brown hue and crystalline texture. It is composed of the same material as diamond, and is in fact supposed to be diamond which has somehow got spoiled in the making. It is found in masses of from one to two pounds weight, and only in the neighbourhood of Bahia, for the lumps of carbon' occasionally met with in South Africa are deficient in harduess, and thus seem to have been arrested at a still earlier stage of their progress towards mineral perfection. Bort,' which is another highly prized in the arts, consists in an aggregation of tiny crystals, mixed, like the black diamonds of Borneo, with a certain proportion of amorphous carbon. We see in it a failure or a freak of nature; and just as the ring of asteroids in the solar system is supposed to represent a single majestic planet, so the forces thus scattered in separate centres of crystallisation would, presumably, under normal conditions, have united to form one radiant jewel.

The manufacturers of diamonds may then have a prosperous career before them, although their successes cause no revolution in the jewel market. There seems no present probability of every laboratory proving a Golconda, and even our remotest posterity will hardly see

mountains' or seas’ of light turned out by the dozen. The vagaries of fashion, far more than the operations of chemists, threaten the supreme position of the queen of gems. Little more than three hundred years ago, the value of the ruby,

In whose core of burning rays

A thousand crimson sunsets are distilled, was eight-fold, and that of the emerald four-fold, that of their radiant sister, and the whirligig of time' may once more revenge them for their present eclipse. But while taste is fickle, nature is immutable: and her productions maintain their qualities unchanged, although we see them with different eyes. Even should the diamond cease to be esteemed the most beautiful of natural substances, it will nevertheless continue to be the most impenetrable, and discarded from the tiara of the princess and the necklace of the ball-room belle, it will maintain its place in the workshop of the engineer and the atelier of the gem-engraver.

AGNES M. CLERKE.

BLUES AND BUFFS.

A SKETCH OF A CONTESTED ELECTION.

CHAPTER XIV.

THE

HE official declaration of the poll was made on the day after its

close, and though the numbers did not precisely correspond with those announced on the previous afternoon, the practical result was the same, and placed Messrs. Barker and Dibbs in the exalted position of members for Shamboro'. What followed was what always followed every contest in that ancient borough. Need it be told how, when both honourable gentlemen, amid cheers and hisses, declared that they should consider themselves henceforth not as the representatives of one party but of all, both were peremptorily commanded to shut up'? Need it be said how whispers of bribery and treating ran through the ranks of both sides--how the Blues swore they would petition against the Buffs, while the Buffs paid a similar prospective compliment to the Blues ? Suffice it to say that the order of the day in Shamboro' was a free indulgence, not only in beer, spirits, and tobacco, but in those luxuries of evil speaking, lying, and slandering, from which all good Christians daily pray to be delivered, and that Blues and Buffs illustrated alike those cardinal virtues of envy, hatred, and uncharitableness which are the ordinary concomitants of all British electioneering.

Poor Jem, who lay with bandaged temples on his uncomfortable four-poster at the Maxwell Arms,' was happily unconscious of the plots and counterplots which were going on. Not so the unhappy Tuppeny, who when he first realised the disaster of which he had been the unwitting instrument, threatened instant self-destruction by dashing the next soda-water bottle in the crate against his own bald head, and when arrested by the waiter in this suicidal effort, rushed to the stables and suspended himself from the lantern ring in the ceiling with a brand-new halter; nor was it until his visage was as black as that of an Ethiopian serenader, that he was cut down and saved from death by Jem's groom, who ever after kept a sharp watch over the poor fellow's movements.

Mr. Pinchum, who always did the proper thing when it did not interfere with his own interest or convenience, called to inquire after Mr. Maxwell, whom, by strict orders of his doctor, no one was to see; but whether he ever saw Jem again or not was of small moment to the wily attorney, who secretly rejoiced at this particular disaster, in the hope that, whether it cost the life of his client or not, it would at all events call off the anxieties of his family from his political disappointment, and distract their attention from the scandalous and discreditable manæuvres by which his own confidential adviser had

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